LTC1693-5 High Speed Single P-Channel MOSFET Driver U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO The LTC®1693-5 drives power P-channel MOSFETs at high speed. The 1.5A peak output current reduces switching losses in MOSFETs with high gate capacitance. Single MOSFET Driver in MSOP Package 1.5A Peak Output Current 16ns Rise/Fall Times at VCC = 12V, CL = 1nF Wide VCC Range: 4.5V to 13.2V CMOS Compatible Input with Hysteresis Input Threshold Is Independent of VCC Driver Input Can Be Driven Above VCC Undervoltage Lockout Thermal Shutdown The LTC1693-5 is a single driver with an output polarity select pin. The MOSFET driver offers VCC independent CMOS input thresholds with 1.2V of typical hysteresis. It can level-shift the input logic signal up or down to the railto-rail VCC drive for the external MOSFET. The LTC1693-5 contains an undervoltage lockout circuit and a thermal shutdown circuit that disables the external P-channel MOSFET gate drive if activated. U APPLICATIO S ■ ■ ■ ■ Power Supplies High Side Drivers Motor/Relay Control Line Drivers Battery Chargers The LTC1693-5 comes in an 8-lead MSOP package. , LTC and LT are registered trademarks of Linear Technology Corporation. U ■ TYPICAL APPLICATIO High Efficiency 1.5A Li-Ion Battery Charger VIN 5V TO 6V MBRS130LT3 POSITION CAPACITOR CLOSE TO LTC1732 332Ω 1µF 332Ω 0.47µF 0.082Ω 0.25W 8 VCC SENSE 4.7Ω 9 LTC1732 3 10 4 CHRG 8 DRV BAT ACPR TIMER PROG 0.1µF AVX 0603ZC104KAT1A 2 1 LTC1693-5CMS8 1 37 POSITION CAPACITOR CLOSE TO SENSE RESISTOR Si2305DS 4 MBRS130LT3 6 18.2k GND SEL 5 7 22µF CERAMIC 22µF CDRH6D38-220NC VCC SEL USE LOW TEMPERATURE COEFFICIENT CAPACITOR CHARGE RATE ≈1.5A (DEPENDING ON VIN AND BATTERY VOLTAGE) 1-CELL Li-Ion BATTERY + – + 100µF 1693-5 TA01 1 LTC1693-5 W U U U W W W ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION (Note 1) Supply Voltage (VCC) .............................................. 14V Inputs (IN, PHASE) ................................... – 0.3V to 14V Driver Output ................................. – 0.3V to VCC + 0.3V Junction Temperature .......................................... 150°C Operating Temperature Range ..................... 0°C to 70°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C ORDER PART NUMBER TOP VIEW IN NC PHASE GND 1 2 3 4 8 7 6 5 VCC OUT NC NC LTC1693-5CMS8 MS8 PACKAGE 8-LEAD PLASTIC MSOP MS8 PART MARKING TJMAX = 150°C, θJA = 200°C/ W LTSG Consult factory for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 12V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN VCC Supply Voltage Range ICC Quiescent Current PHASE = 12V, IN = 0V ● ICC(SW) Switching Supply Current COUT = 4.7nF, fIN = 100kHz ● TYP MAX UNITS 13.2 V 360 550 µA 7.2 10 mA 2.6 3.1 V 4.5 200 Input VIH High Input Threshold ● 2.2 VIL Low Input Threshold ● 1.1 IIN Input Pin Bias Current ● VPH PHASE Pin High Input Threshold ● IPH PHASE Pin Pull-Up Current PHASE = 0V VOH High Output Voltage VOL Low Output Voltage RONL Output Pull-Down Resistance 2.85 Ω RONH Output Pull-Up Resistance 3.00 Ω IPKL Output Low Peak Current 1.70 A IPKH Output High Peak Current 1.40 A 1.4 1.7 V ±0.01 ±10 µA 4.5 5.5 6.5 V ● 10 20 45 µA IOUT = –10mA ● 11.92 11.97 IOUT = 10mA ● Output 30 V 75 mV Switching Timing (Note 2) tRISE Output Rise Time COUT = 1nF COUT = 4.7nF ● ● 17.5 48.0 35 85 ns ns tFALL Output Fall Time COUT = 1nF COUT = 4.7nF ● ● 16.5 42.0 35 75 ns ns tPLH Output Low-High Propagation Delay COUT = 1nF COUT = 4.7nF ● ● 38.0 40.0 70 75 ns ns tPHL Output High-Low Propagation Delay COUT = 1nF COUT = 4.7nF ● ● 32 35 70 75 ns ns Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: All AC timing specificatons are guaranteed by design and are not production tested. 2 LTC1693-5 U W TYPICAL PERFOR A CE CHARACTERISTICS IN Threshold Voltage vs Ambient Temperature 2.75 3.00 2.50 INPUT THRESHOLD VOLTAGE (V) INPUT THRESHOLD VOLTAGE (V) TA = 25°C VIH 2.25 2.00 1.75 1.50 VIL 1.25 1.00 5 6 7 9 8 VCC (V) 11 10 1.4 VCC = 12V 2.75 VIH 2.50 2.25 2.00 1.75 1.50 VIL 1.25 1.00 – 50 –25 12 IN Threshold Hysteresis vs Ambient Temperature 0 50 75 100 25 AMBIENT TEMPERATURE (°C) 1693-5 G01 VIH-VIL 1.1 1.0 0.9 0.8 – 50 125 5 VPH(H) 2 125 Rise/Fall Time vs Ambient Temperature 19 18 VCC = 12V COUT = 1nF fIN = 100kHz tRISE 17 20 tRISE TIME (ns) 4 3 25 75 100 – 25 0 50 AMBIENT TEMPERATURE (°C) 1693-5 G03 TA = 25°C COUT = 1nF fIN = 100kHz 22 TIME (ns) PHASE THRESHOLD VOLTAGE (V) 1.2 20 24 TA = 25°C 18 tFALL 16 tFALL 16 15 14 13 14 12 1 12 0 10 5 6 7 9 8 VCC (V) 10 11 12 11 5 6 7 9 8 VCC (V) 10 1693-5 G04 11 12 55 TA = 25°C VCC = 12V 100 fIN = 100kHz Propagation Delay vs Ambient Temperature 45 TIME (ns) 40 60 40 45 40 tPHL 35 30 25 1000 30 15 0 100 COUT (pF) tPHL 25 tFALL 10 tPLH 35 20 tRISE 1 VCC = 12V COUT = 1nF fIN = 100kHz tPLH TIME (ns) 80 50 TA = 25°C COUT = 1nF fIN = 100kHz 50 125 1693-5 G06 Propagation Delay vs VCC 120 20 10 50 25 0 75 100 –50 –25 AMBIENT TEMPERATURE (°C) 1693-5 G05 Rise/Fall Time vs COUT TIME (ns) 1.3 Rise/Fall Time vs VCC VPH(L) VCC = 12V 1693-5 G02 PHASE Threshold Voltage vs VCC 6 INPUT THRESHOLD HYSTERESIS (V) IN Threshold Voltage vs VCC 10000 1693-5 G07 10 5 6 7 8 9 VCC (V) 10 11 12 1693-5 G08 20 – 50 – 25 50 100 25 75 0 AMBIENT TEMPERATURE (°C) 125 1693-5 G09 3 LTC1693-5 U W TYPICAL PERFOR A CE CHARACTERISTICS Output Saturation Voltage vs Temperature Propagation Delay vs COUT 200 OUTPUT SATURATION VOLTAGE (mV) TA = 25°C VCC = 12V fIN = 100kHz TIME (ns) 40 tPLH 30 tPHL Quiescent Current vs VCC 350 VCC = 12V TA = 25°C VIN = 0V VOH (50mA) wrt VCC QUIESCENT CURRENT (µA) 50 150 VOL (50mA) 100 50 VOH (10mA) wrt VCC 300 250 200 150 VOL (10mA) 20 1 100 COUT (pF) 10 1000 10000 0 – 55 – 35 –15 1693-5 G10 100 200 60 VOL (mV) SWITCHING SUPPLY CURRENT (mA) TA = 25°C VCC = 12V 250 70 50 40 30 750kHz 20 10 200kHz 100kHz 25kHz VOL 150 100 50 500kHz 0 0 1 10 100 COUT (pF) 1000 0 10000 10 20 30 40 50 60 70 80 90 100 OUTPUT CURRENT (mA) 1693-5 G13 1693-5 G14 Thermal Derating Curve VOH vs Output Current 1400 TA = 25°C VCC = 12V TJ = 125°C 1200 POWER DISSIPATION (mW) 300 VOH (mV) 250 VOH 200 150 100 50 1000 800 600 400 200 0 0 10 20 30 40 50 60 70 80 90 100 OUTPUT CURRENT (mA) 1693-5 G15 4 10 VOL vs Output Current 80 350 9 8 VCC (V) 11 12 1693-5 G12 300 TA = 25°C VCC = 12V 90 7 6 1693-5 G11 Switching Supply Current vs COUT 100 5 5 25 45 65 85 105 125 TEMPERATURE (°C) 0 – 55 – 35 –15 5 25 45 65 85 105 125 AMBIENT TEMPERATURE (°C) 1693-5 G16 LTC1693-5 U U U PIN FUNCTIONS IN (Pin 1): Driver Input. The input has VCC independent thresholds with hysteresis to improve noise immunity. GND (Pin 4): Driver Ground. Connect to a low impedance ground. The VCC bypass capacitor should connect directly to this pin. NC (Pins 2, 5, 6): No Connect. OUT (Pin 7): Driver Output. PHASE (Pin 3): Output Polarity Select. Connect this pin to VCC or leave it floating for noninverting operation. Ground this pin for inverting operation. The typical PHASE pin input current when pulled low is 20µA. VCC (Pin 8): Power Supply Input. The source of the external P-MOSFET should also connect directly to this pin. This minimizes the AC current path and improves signal integrity. WU W TI I G DIAGRA INPUT RISE/FALL TIME < 10ns INPUT VIH VIL NONINVERTING OUTPUT OPERATION 90% 10% tr tPLH INVERTING OUTPUT OPERATION tf tPHL 90% 10% tf tPHL tr tPLH 1693-5 TD 5 LTC1693-5 U W U U APPLICATIONS INFORMATION Overview The LTC1693-5 single driver allows 3V- or 5V-based digital circuits to drive power P-channel MOSFETs at high speeds. A power MOSFET’s gate-charge loss increases with switching frequency and transition time. The LTC1693-5 is capable of driving a 1nF load with 16ns rise and fall times using a VCC of 12V. This eliminates the need for higher voltage supplies, such as 18V, to reduce the gate charge losses. The LTC1693-5’s 360µA quiescent current is an order of magnitude lower than most other drivers/buffers. This improves system efficiency in both standby and switching operation. Since a power MOSFET generally accounts for the majority of power loss in a converter, addition of the LT1693-5 to a high power converter design greatly improves efficiency, using very little board space. Input Stage The LTC1693-5 employs 3V CMOS compatible input thresholds that allow a low voltage digital signal to drive standard power P-channel MOSFETs. The LTC1693-5 incorporates a 4V internal regulator to bias the input buffer. This allows the 3V CMOS compatible input thresholds (VIH = 2.6V, VIL = 1.4V) to be independent of variations in VCC. The 1.2V hysteresis between VIH and VIL eliminates false triggering due to ground noise during switching transitions. The LTC1693-5’s input buffer has a high input impedance and draws less than 10µA during standby. Output Stage The LTC1693-5’s output stage is essentially a CMOS inverter, as shown by the P- and N-channel MOSFETs in Figure 1 (P1 and N1). The CMOS inverter swings rail-torail, giving maximum voltage drive to the load. This large voltage swing is important in driving external power P-channel MOSFETs, whose RDS(ON) is inversely proportional to its gate overdrive voltage (VGS – VT). The LTC1693-5’s peak output currents are 1.4A (P1) and 1.7A (N1) respectively. The N-channel MOSFET (N1) has higher current drive capability so it can charge the power MOSFET’s gate capacitance during high-to-low signal transitions. When the power MOSFET’s gate is pulled high by the LTC1693-5, its drain voltage is pulled low by its load (e.g., a resistor or inductor). The slew rate of the drain voltage causes current to flow back to the MOSFETs gate through its gate-to-drain capacitance. If the MOSFET driver does not have sufficient source current capability (low output impedance), the current through the power MOSFET’s Miller capacitance (CGD) can momentarily pull the gate low, turning the MOSFET back on. Rise/Fall Time Since the power MOSFET generally accounts for the majority of power lost in a converter, it’s important to quickly turn it either fully “on” or “off” thereby minimizing the transition time in its linear region. The LTC1693-5 has rise and fall times on the order of 16ns, delivering about 1.4A to 1.7A of peak current to a 1nF load with a VCC of only 12V. The LTC1693-5 rise and fall times are determined by the peak current capabilities of P1 and N1. The predriver, shown in Figure 1 driving P1 and N1, uses an adaptive method to minimize cross-conduction currents. This is done with a 6ns nonoverlapping transition time. N1 is fully turned off before P1 is turned-on and vice-versa using this 6ns buffer time. This minimizes any cross-conduction currents while N1 and P1 are switching on and off yet is short enough to not prolong their rise and fall times. VCC LTC1693-5 P1 CGS OUT POWER MOSFET N1 CGD GND LOAD 1693-5 F01 Figure 1. Capacitance Seen by OUT During Switching 6 LTC1693-5 U U W U APPLICATIONS INFORMATION UVLO and Thermal Shutdown Bypassing and Grounding The LTC1693-5’s UVLO detector disables the input buffer and pulls the output pin to VCC if VCC < 4V. The output remains off from VCC = 1V to VCC = 4V. This ensures that during start-up or improper supply voltage values, the LTC1693-5 will keep the output power P-channel MOSFET off. LTC1693-5 requires proper VCC bypassing and grounding due to its high speed switching (ns) and large AC currents (A). Careless component placement and PCB trace routing may cause excessive ringing and under/overshoot. The LTC1693-5 also has a thermal detector that similarly disables the input buffer and pulls the output pin to VCC if junction temperature exceeds 145°C. The thermal shutdown circuit has 20°C of hysteresis. This thermal limit helps to shut down the system should a fault condition occur. Input Voltage Range LTC1693-5’s input pin is a high impedance node and essentially draws neligible input current. This simplifies the input drive circuitry required for the input. The LTC1693-5 typically has 1.2V of hysteresis between its low and high input thresholds. This increases the driver’s robustness against any ground bounce noises. However, care should still be taken to keep this pin from any noise pickup, especially in high frequency switching applications. In applications where the input signal swings below the GND pin potential, the input pin voltage must be clamped to prevent the LTC1693-5’s parastic substrate diode from turning on. This can be accomplished by connecting a series current limiting resistor R1 and a shunting Schottky diode D1 to the input pin (Figure 2). R1 ranges from 100Ω to 470Ω while D1 can be a BAT54 or 1N5818/9. To obtain the optimum performance from the LTC1693-5: A. Mount the bypass capacitors as close as possible to the VCC and GND pins. The leads should be shortened as much as possible to reduce lead inductance. It is recommended to have a 0.1µF ceramic in parallel with a low ESR 4.7µF bypass capacitor. For high voltage switching in an inductive environment, ensure that the bypass capacitors’ VMAX ratings are high enough to prevent breakdown. This is especially important for floating driver applications. B. Use a low inductance, low impedance ground plane to reduce any ground drop and stray capacitance. Remember that the LTC1693-5 switches 1.5A peak currents and any significant ground drop will degrade signal integrity. C. Plan the ground routing carefully. Know where the large load switching current is coming from and going to. Maintain separate ground return paths for the input pin and output pin. Terminate these two ground traces only at the GND pin of the driver (STAR network). D. Keep the copper trace between the driver output pin and the load short and wide. VCC LTC1693-5 INPUT SIGNAL GOING BEL0W GND PIN POTENTIAL R1 D1 IN PARASITIC SUBSTRATE DIODE 1693-5 F02 GND Figure 2. Input Protection Against Negative Input Signals Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 7 LTC1693-5 U PACKAGE DESCRIPTION Dimensions in inches (millimeters) unless otherwise noted. MS8 Package 8-Lead Plastic MSOP (LTC DWG # 05-08-1660) 0.118 ± 0.004* (3.00 ± 0.102) 8 7 6 5 0.118 ± 0.004** (3.00 ± 0.102) 0.193 ± 0.006 (4.90 ± 0.15) 1 2 3 4 0.043 (1.10) MAX 0.007 (0.18) 0.034 (0.86) REF 0° – 6° TYP 0.021 ± 0.006 (0.53 ± 0.015) SEATING PLANE 0.009 – 0.015 (0.22 – 0.38) 0.0256 (0.65) BSC 0.005 ± 0.002 (0.13 ± 0.05) MSOP (MS8) 1100 * DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LTC1154 High Side Micropower MOSFET Drivers Internal Charge Pump, 4.5V to 48V Supply Range, tON = 80µs, tOFF = 28µs LTC1155/LTC1156 Dual Micropower High/Low Side Drivers with Internal Charge Pump 4.5V to 18V Supply Range LTC1157 3.3V Dual Micropower High/Low Side Driver 3.3V or 5V Supply Range LT 1160/LT1162 Half/Full Bridge N-Channel Power MOSFET Driver Dual Driver with Topside Floating Driver, 10V to 15V Supply Range LT1161 Quad Protected High Side MOSFET Driver 8V to 48V Supply Range, tON = 200µs, tOFF = 28µs LTC1163 Triple 1.8V to 6V High Side MOSFET Driver 1.8V to 6V Supply Range, tON = 95µs, tOFF = 45µs LT1339 High Power Synchronous DC/DC Controller Current Mode Operation Up to 60V, Dual N-Channel Synchronous Drive LTC1735 High Efficiency, Low Noise Current Mode Step-Down DC/DC Controller 3.5V to 36V Operation with Ultrahigh Efficiency, Dual N-Channel MOSFET Synchronous Drive LTC1693-1/LTC1693-2/ LTC1693-3 Single/Dual N-Channel MOSFET Drivers 1.5A Peak Output Current, Dual Drivers Permit High/Low Side Drive LTC1981/LTC1982 SOT-23 High Side Drivers Integrated Voltage Triplers, 10µA Quiescent per Driver ® 8 Linear Technology Corporation 16935f LT/TP 0101 4K • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com LINEAR TECHNOLOGY CORPORATION 2001